Abstract: Since the 1980s, the sex ratio at birth (SRB) in China has been abnormally high for more than 40 years, and it might take 30 years to return to normal. The 70year SRB transition profoundly affects the population dynamics. Based on the most recent data on SRB, fertility and mortality, this study focuses on the impact of the SRB transition on the age structure in China. The results show that abnormally high SRB has reduced the number of births and thus the population size, thereby has sped up population ageing. Normalizing SRB can alleviate population ageing. Therefore, normalizing SRB could be taken as one of the strategies to actively cope with population ageing, aside from improving gender inequality.

Keywords: Sex Ratio at Birth, Transition of Sex Ratio at Birth, Population Ageing

摘要： 从1980年代开始，中国出生性别比失衡已经持续40余年，预计到2050年左右才能恢复正常。长达70年的出生性别比转变对中国人口和社会都产生深远的影响。以往研究主要集中探讨性别失衡问题，对出生性别比升高加剧人口老龄化的关注较少。为此，利用新近估计的中国出生性别比、生育率和死亡率数据，借助人口模拟预测和稳定人口比较分析的方法对中国出生性别比转变的人口老龄化后果进行深入考察。研究发现，出生性别比上升不仅会减少女婴出生数，还会减少男婴出生数，由此造成人口规模的下降并加剧了中国的人口老龄化。引导出生性别比尽快回归正常可以缓解人口老龄化，继续加强出生性别比治理可以在中国积极应对人口老龄化的过程中起到重要作用。

关键词: 出生性别比, 出生性别比转变, 人口老龄化